Home – Home – Jornals – Thermophysics and Aeromechanics 2005 number 1

Results of the numerical modelling of the heat island (heat spot) effect on the atmospheric boundary layer (ABL) structure are presented. Fully explicit algebraic models obtained with the aid of symbolic algebra from the transport equations for momentum and heat fluxes in the approximation of a weakly equilibrium turbulence are used to compute the turbulent momentum and heat fluxes. The three-parameter E -  ((²( model of thermally stratified turbulence is used to close the algebraic expressions for fluxes. The conducted two-dimensional computational test for the 24-hour ABL evolution shows that the mesoscale turbulence model of the third level of closure is capable of reproducing the most important structural ABL peculiarities over the underlying surface with a heat island, including those of them, which are inaccessible to the k -  -model of turbulence. The results obtained agree with measurement data and numerical results of other authors.